Add getTool method for AsyncMcpToolCallback in order to get toolName witch has been prefixed in getToolDefinition

[shishuiwuhen2009]

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[markpollack]

what about this instead, i assume you want to get easy access to the 'original' toolname before the prefix was added?

public String getOriginalToolName() {
    return this.tool.name();
}

This would:

• Provide access to the original tool name
• Maintain better encapsulation
• Be more explicit about intent
• Not expose internal implementation details

[shishuiwuhen2009]

Thank you so much for your suggestions!

[shishuiwuhen2009]

fix in #4204